Electrical plug connector



y 15, 1952 H. w. SNYDER 2,603,680

ELECTRICAL PLUG CONNECTOR Filed March 1, 1950 FIG. 1.

FIG- 6- 2 Fla 1. FIG. 8.

INVENTOR.

' H ETTIH William Engder BY A mas/Q1 ATTORNEYS.

Patented July 15, 1952 I. U NITED STAT-ES PATENT OFFICE v 2,603,680ELECTRICAL PLUG CONNECTOR 7 "Henry William Snyder, Bzeman, Mont.

Application March 1, 1950, Serial No. 146,970

' 3 Claims.

This invention relates to an-irnprovediorm of electrical plug connectorparticularly for heavy current carrying flexible cables adaptedforwelding lead conductors and other uses where such plugsmay be employed.

The primary object of this invention is to provide an improvedsolderless electrical plug connector which may be easily and permanentlyattached to the end of flexibleorextra flexible electrical cable andprovide a connection between cable and plug of low electrical resistanceand good 'mechanical strength. -Other solderless type plug connectorseither are of the screw type which may loosen-and becomedisassembled orcause heating and arcing among their various parts, or else specialtools are required for permanent assembly of .thevariousparts. Among theadvantages of this invention are: simplicity of design for ease inmanufacture and assembly. Assembly may-be done with only an arbor pressend for a suitable-length approximately the length of the clampingsleeve, as shown .in Ei 2. Plug l0 andfsocket H are .preferably made ofbrass or bronzehaving a high electrical conductivity, such as is usualfor electrical plug connectors, and clamping sleeve I2 is preferably Mcopper tubing having a wall thickness of ap- (or common table vise in anemergency), no

special tools being needed. d

Other objects and advantages will appear to those skilled-in the artfrom the following description, supplemented by the drawingsillustrating highly satisfactory embodiments of the invention, andforming apart of this specification.

:In the drawings:

:Fig. .1.is an exploded side view of the plug conne'ctorrelements inaccordance with my invention.

Fig.2.is a side view of the connector elements, with parts inlongitudinalse'ction, showing the parts with the end of a-cableupon'which they are to be applied.

Figs. 3 and 4' are similar side views illustrating successive-positionsof the elements as the plug member is pressed into position.

Fig. 5 is a similar side view showing the plug member in its finalposition, and the plug connector elements secured on a flexible cable inaccordance with my invention.

Fig. 6 is a leftend view of theplug member.

Fig. '7 is aside view of a modified form of plug member.

Fig. 8 is a'left-end view-of the plugmember shown in Fig. I.

Referring to the drawings wherein similar'referance characters designatecorresponding parts throughout the several views, the solderlesselsetrical plug connector or cable terminal connector in accordance withmy invention consists of three members, aplug H), a shell '0I socket Hand a clamp sleeve l2 for application to a flexible. type of cablel3from the end of which insulation [4 hasbeen removed tobarethe-cablewires atthe proximatelyone thirty-second inch and suitableinside diameter to slide freelyover the stripped end l5 of cable l3. Thecopper clamping sleeve is dead-soft vannealedso that .it may be readilycrimped or deformed into gripping engagement with the bared wires'at theend H; of the cable.

The shell or socket member I l, at. times hereinafter referred to as afirst conductor element is machined or otherwise formed preferably fromtube stock, of such dimensionsthat no machining is necessary .on theoutside. The tube socket preferably has a bore N5 of such, diameter thatthe strippedend l5 of cable [3 maybe freely inserted through it withoutrequiring machining operations. Theouterendof the shellor socket l l'hasa larger concentricbore ll machined toa close tolerance so that ,a tightfit (otherwise' designated as a. class6 fit) will lee-provided betweenitand the cylindricalinner end 18' of the plug member. The angle of abevel -shoulder l9 between bores l6 and i1 .is shown as sixty degreeswith respect to the axis of the shell portion, though thisangle may bevaried l Plug member [0, at times hereinafter referred to as a secondconductor element, ispreferably formed from standard rodstock of therequired diameter providing the ,cylindricalportion l8 thereof, asmentioned above, or, it may be formed from other stock and machined sothat the cylindrical portion IS with the required diameter is provided.The outerend'lfi may be tapered so as to fit standardplug receptaclesandthe inner end is machined to a diameter slightly .less than the innerdiameter of clamping sleeve l2 to provide asmall shoulder 20 thereonwhich facilitates theassembly of the plug connector on .the endof aflexible cable.

While plug Ill provided with theshoulderZfl is preferable and requiresinits formation only a simple minor operation in an automatic screwmachine which does. not add. appreciably 'to manufacturing costs, theplug 2| shown in Figs. 7 and 8, having a flat end 22, may be .used inplace of such a shouldered plug 10. Plug-2]: re: quires less machinework.

Plug l0 as illustrated, and above described, is provided with a taperedplugging end. However it will be understood that any conventionalpformconnector upon the end of the flexible or extraflexible electrical cableI23, thefcable end must first be stripped of insulation I II for asuitable length as previously explained. In the drawings this length isshown as being approximately the same as the length of the clampingsleeve [2, but this is a matter of design which will depend uponthelength of bore I6, diameter and length of largeconcentric bore I! ofthe shell or socket I I, and the wall thickness'of clamping sleeve 12.

I have found that satisfactory proportions of- ;the various parts may beas follows: length of socket element II, approximately six times thediameter of stripped end I5 of the flexible electrical cable; length ofbore I6 of the socket,

approximately equal the diameter of the stripped end' I5 of theelectricalcable; length of clamping sleeve I2 before deformation,approximately four and one-half times the diameter of the stripped endl5 of the electrical cable; and diameter of large bore I1 of socket I l,approximately one and,

one-half times the diameter of the stripped end I5 of the electricalcable. When these proportionsare'used and the cable stripped asdescribed above,,the stripped end I5 of the cable will extendapproximately half way through the larger bore I"! of the socket II wheninserted through the smallerbore I6 as shown in Fig. 2 where the portionI is shown inserted intothe outer end of the shell or socket I I inposition to engage the clampingsleeve overthe shoulder 20.

With the stripped end I of the cable held in place (by hand or otherconvenient means) and the-inner end 23 of theshell or socket II sup-.ported by angle brackets or other convenient means, pressure is appliedto end surface 24 of the plug) or 2|) bymeans of the plunger ofv anarbor press or other convenient means. Under this pressure the plugIdis' forced into large concentric bore I! of the shell portion and theend surface of. the plug surrounding shoulder 20 engages and applieslongitudinal pressure upon the clamping sleeve I2. Under the influenceof this longitudinal pressure, the inner end-2 5 of the clamping sleeveis forced against bevel shoulder IQ of the shell or socket II anddeformedagainst. the stripped end l5 3. Whenno further'deformation ispossible in this direction, the wall of the clamping sleeve I2 4 sleeveuntil the same is. completely folded and compressed substantially asshown at 21 in Fig. 5, and the stripped end I5 of the flexibleelectrical cable is clamped in place by means of the radial pressurepreviously noted and also by the pinching of the cable strands betweenthe folds of the clamping sleeve.

When the pressing operation is completed the plug Hi is firmly grippedwithin the larger concentric bore I'I of the socket member I I by reasonof the tight fit between this larger concentric j bore l7 of the socketandthe cylindrical portion I8 0f the shell or socket ll. As shown inFig. 5

' both the end of clamping sleeve I2 and frayed ends 2601 the strippedportion I5 of cable I3 are in intimate contact or engagement with theend'of plug I0, which insures a good electrical contact between thewires of the cable and the plug, and tendsto solidify the connectionbetween the socket II and plug .III.

From the foregoing it will be seen that the cable connectionillustrated, particularly with a plug connector, has numerous advantagesin providing an electrical connection with terminal connecting members,or as the cable terminal connection in other forms of connections forflexible stranded wire cables, and it is to be understood that theinvention includes such connections within the scope of the claims.

I claimi 1. A connector for the terminal of an electric cable includinga deformable cylindrical tubular clamping sleeve having an internaldiameter slightly greater than the bared conductor end of the cable tobe inserted thereinto, a first con- 4 nector element having alongitudinal bore therethrough of'a diameter through which the baredconductor end may pass at one end and into the clamping sleeve and of adiameter greater than the sleeve at its other end so that one end 7 ofthe sleeve may be inserted therein and over the of the flexibleelectricalcable as shown in Fig.

collapses inward and folds against the stripped end: l5 of the flexibleelectrical cable, and also against the wall of the larger bore ll of theshell v or socket'l I substantially as shown in Fig and exerts asubstantial radial pressure between cable end-l5 and the socket bore. Inthe process of 1 folding inward,,the clamping sleeve I2 pulls andpinches some strands. of the stripped'end I5 1 1 of the flexibleelectrical cable I3 causing the." end'to fray substantially as shown at25 in Fig.

4. Continued pressure upon surface 2 4 of, the plug It) causes repeatedfolding of the clamping end of the conductor, means on said element foreffecting a crimping of said end of the sleeve into the conductor, asecond connector element having a cylindrical end portion of a diameterto provide a tight fit in the increased diameter bore of said firstconnector element, and an extension of reduced diameter on the end ofthe second connector element for entering the opposite end of the sleeveproviding a guide and an abutment so that when this second element isdriven into the first element it will compress the sleeve to deform itso as to alternately engage and grip the bared conductor and the surfaceof the bore so as to lock the parts in assembled relation.

2. A connector for the terminal of an electric cable including adeformable cylindrical tubular clamping sleeve having an internaldiameter slightly greater than the bared conductor end of thev cable tobe inserted thereinto, a first connector element having a longitudinalbore therethrough of a diameter through which the bared conductor endmay pass at one end and into the clamping sleeve and of a diametergreater than the sleeve at its otherend so that the sleeve may beinserted therein and over the end of the conductor, said element havinga beveled shoulder at the juncture of the larger smaller "diameters ofthe bore, tapering from the smaller diameter and providing a formingsurface for the clamping sleeve so that upon application of endwisepressure on the sleeve, its end engaging this tapering surface'will becontracted and caused to bite into the bared conductor, and a secondconnector element having a cylindrical end portion of a diameter toprovide a tight fit in the increased diameter bore of said firstconnector element so that when this second element is driven into.thefirst element it will compress the sleeve to deform it so as toalternately engage and grip the bared conductor and the surface of thebore so as to lock the parts in assembled relation.

3. A connector for the terminal of an electric cable including adeformable cylindrical tubular clamping sleeve having an internaldiameter slightly greater than the bared conductor end of the cable tobe inserted thereinto, a first connector element having a longitudinalbore therethrough of a diameter through which the bared v conductor endmay pass at one end and into the clamping sleeve and of a diametergreater than the sleeve at its other end so that one end of the sleevemay be inserted therein and over the end of the conductor, and a secondconnector element having a cylindrical end portion of a diameter toprovide a tight fit in the increased diameter bore of said firstconnector element, an extension of reduced diameter on the end of thesecond connector element providing an abutment 6 for engaging the end ofthe conductor which will enter the'end of the sleeve and afford a guidetherefor and an annular cavity between the extension and saidlarger boreof the first connector element, said cavity providing a shoulder betweenthe extension and end of the second connector element affording anabutting surface for the opposite end of the sleeve so that when thissecond element is driven into the first element it will compress thesleeve to deform it so asto'alternately engage and grip the baredconductor and the surface of the bore so'as to lock the parts inassembled relation.

HENRY WILLIAM SNYDER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,643,110 Briggs Sept. 20, 19272,076,072 Douglas Apr. 6, 1937 2,394,020 Soreny Feb. 5, 1946

